package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.extension.conditions.query.LambdaQueryChainWrapper;
import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.Voucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import io.netty.util.SuppressForbidden;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.connection.stream.*;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.time.Duration;
import java.time.LocalDateTime;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
@Slf4j
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {
    @Resource
    private ISeckillVoucherService seckillVoucherService;
    @Resource
    private StringRedisTemplate stringRedisTemplate;
    @Resource
    private RedissonClient redissonClient;
    private IVoucherOrderService proxy;
    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;
    static {
        SECKILL_SCRIPT = new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }

    private static final ExecutorService SECKILL_ORDER_EXEXUTOR = Executors.newSingleThreadExecutor();
    @PostConstruct
    private void init(){
        SECKILL_ORDER_EXEXUTOR.submit(new VoucherOrderHandler());
    }
    private class VoucherOrderHandler implements Runnable{
        String queueName = "stream.orders";
        @Override
        public void run() {
            while(true){

                try {
                    //1.获取消息队列中的订单信息
                    List<MapRecord<String, Object, Object>> list = stringRedisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1).block(Duration.ofSeconds(2)),
                            StreamOffset.create(queueName, ReadOffset.lastConsumed())
                    );
                    //判断消息获取是否成功
                    if (list == null || list.isEmpty()){
                        //如果获取失败，说明没有消息，继续下一次循环
                        continue;
                    }
                    //如果获取成功，可以下单
                    //解析消息中的订单信息
                    MapRecord<String, Object, Object> record = list.get(0);
                    Map<Object, Object> values = record.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);
                    handleVoucherOrder(voucherOrder);
                    //ack确认
                    stringRedisTemplate.opsForStream().acknowledge(queueName,"g1",record.getId());
                } catch (Exception e) {
                    log.error("处理订单异常",e);
                    try {
                        handlePendingList();
                    } catch (InterruptedException ex) {
                        throw new RuntimeException(ex);
                    }
                }
                //2.创建订单
            }
        }

        private void handlePendingList() throws InterruptedException {
            while(true){

                try {
                    //1.获取消息队列中的订单信息pendinglist
                    List<MapRecord<String, Object, Object>> list = stringRedisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1),
                            StreamOffset.create(queueName, ReadOffset.from("0"))
                    );
                    //判断消息获取是否成功
                    if (list == null || list.isEmpty()){
                        //如果获取失败，说明PendingList没有消息，结束循环循环
                        break;
                    }
                    //如果获取成功，可以下单
                    //解析消息中的订单信息
                    MapRecord<String, Object, Object> record = list.get(0);
                    Map<Object, Object> values = record.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);
                    handleVoucherOrder(voucherOrder);
                    //ack确认
                    stringRedisTemplate.opsForStream().acknowledge(queueName,"g1",record.getId());
                } catch (Exception e) {
                    log.error("处理订单异常",e);
                    Thread.sleep(20);
                }
                //2.创建订单
            }
        }
    }
//    private class VoucherOrderHandler implements Runnable{
//        @Override
//        public void run() {
//            while(true){
//                //1.获取队列中的订单信息
//                try {
//                    VoucherOrder voucherOrder = orderTasks.take();
//                    handleVoucherOrder(voucherOrder);
//                } catch (Exception e) {
//                    log.error("处理订单异常",e);
//                }
//                //2.创建订单
//            }
//        }
//    }

    private void handleVoucherOrder(VoucherOrder voucherOrder) {
        //获取用户
        Long userId = voucherOrder.getUserId();
        //1.尝试创建锁对象
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        //2.获取锁
        boolean islock = lock.tryLock();
        //3.判断是否获取锁成功
        if (!islock) {
            //获取锁失败
            log.info("不允许重复下单");
            return ;
        }
        try {
            proxy.createVoucherOrder(voucherOrder);
        } catch (IllegalStateException e) {
            throw new RuntimeException(e);
        } finally {
            lock.unlock();
        }
    }

    @Resource
    private RedisIdWorker redisIdWorker;
    public Result seckillVoucher(Long voucherId) {
        //获取用户
        Long userId = UserHolder.getUser().getId();
        //获取订单
        long orderId = redisIdWorker.nextId("order");
        //1.执行lua脚本、
        Long result = stringRedisTemplate.execute(
                SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(), userId.toString(),String.valueOf(orderId)
        );
        //2.判断结果是否为0
        int i = result.intValue();
        //2.1 不为0，代表没有购买资格
        if (i != 0){
            return Result.fail(i == 1 ? "库存不足" : "不能重复下单");
        }
        //2.2 为0,有购买资格，把下单信息保存到阻塞队列中

        proxy = (IVoucherOrderService) AopContext.currentProxy();
        //3.返回订单id
        return  Result.ok(orderId);

    }
//    public Result seckillVoucher(Long voucherId) {
//        //获取用户
//        Long userId = UserHolder.getUser().getId();
//        //1.执行lua脚本、
//        Long result = stringRedisTemplate.execute(
//                SECKILL_SCRIPT,
//                Collections.emptyList(),
//                voucherId.toString(), userId.toString()
//        );
//        //2.判断结果是否为0
//        int i = result.intValue();
//        //2.1 不为0，代表没有购买资格
//        if (i != 0){
//            return Result.fail(i == 1 ? "库存不足" : "不能重复下单");
//        }
//        //2.2 为0,有购买资格，把下单信息保存到阻塞队列中
//        long orderId = redisIdWorker.nextId("order");
//        VoucherOrder voucherOrder = new VoucherOrder();
//        voucherOrder.setId(orderId);
//        voucherOrder.setUserId(userId);
//
//        voucherOrder.setVoucherId(voucherId);
//        orderTasks.add(voucherOrder);
//
//        proxy = (IVoucherOrderService) AopContext.currentProxy();
//        //3.返回订单id
//        return  Result.ok(orderId);
//
//    }
//    @Override

//    public Result seckillVoucher(Long voucherId) {
//
//        SeckillVoucher seckillShop = seckillVoucherService.getById(voucherId);
//        LocalDateTime endTime = seckillShop.getEndTime();
//        LocalDateTime beginTime = seckillShop.getBeginTime();
//        if (LocalDateTime.now().isBefore(beginTime)){
//            return Result.fail("活动未开始");
//        }
//        if (LocalDateTime.now().isAfter(endTime)){
//            return Result.fail("活动时间已过");
//        }
//        Integer stock = seckillShop.getStock();
//        if (stock<=0){
//            return Result.fail("库存不足。。。");
//        }
//        Long id = UserHolder.getUser().getId();
//        //1.尝试创建锁对象
////        SimpleRedisLock lock = new SimpleRedisLock("order" + id, stringRedisTemplate);
//        RLock lock = redissonClient.getLock("lock:order:" + id);
//        //2.获取锁
//        boolean islock = lock.tryLock();
//        //3.判断是否获取锁成功
//        if (!islock) {
//            //获取锁失败
//            return Result.fail("一个人只允许下一单");
//        }
//        try {
//            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
//            return proxy.getResult(id,voucherId);
//        } catch (IllegalStateException e) {
//            throw new RuntimeException(e);
//        } finally {
//            lock.unlock();
//        }
//
//    }
    @Transactional
    public void createVoucherOrder(VoucherOrder voucherOrder) {
        Long userId = voucherOrder.getUserId();
        int count = query().eq("user_id", userId).eq("voucher_id", voucherOrder.getVoucherId()).count();
        if (count>=1){
            log.error("用户已经购买过一次");
            return ;
        }
        //扣减库存
        boolean success = seckillVoucherService.update().setSql("stock = stock-1")
                .eq("voucher_id", voucherOrder.getVoucherId()).gt("stock",0)
                 .update();

        if (!success){
            log.error("库存不足！！！");
            return ;
        }



        save(voucherOrder);

    }
}
